This time it was for the L.A. rap/dance/pop duo's ode to self-infatuation, "Sexy and I Know It" — an infectiously simple dance-floor ditty with a relentless rhythm and a video that has been viewed more than 188 million times on YouTube. Last year's ubiquitous hit, "Party Rock Anthem," currently at No. 6, is a truth-in-advertising title if there ever was one (347 million views).

Created by an uncle-nephew team who rose in Los Angeles' club scene in the mid '00s and made a splash with their in-your-face debut album, "Party Rock," in 2009, "Sexy and I Know It," from the 2011 conciliatory follow-up, "Sorry for Party Rocking," has worked its way into America's subconscious through repetition and sticky, simple chords. It's a song that — even heard faintly while passing Forever 21 at the mall — can ruin an entire weekend by looping in your head.

It's getting harder and harder to ignore LMFAO and less certain that it'll ever go away. For the last three years the group, which consists of Redfoo (Stefan Kendal Gordy, 36) and SkyBlu (Skyler Austin Gordy, 25), has surpassed even the most snobbish haters' worst fears. After rising through the pop music ranks with a combination of iTunes sales, club dates, funny videos and, most important, key placement in reality shows including "Jersey Shore," "Real World: Cancun" (they were a featured story line) and the early Kardashian hit "Kourtney and Khloe Take Miami," 2011 was their breakout year, and 2012 looks to push them even further. Last week they were the second most subscribed YouTube music channel in Saudi Arabia, Kenya, Tunisia, Ireland, Russia and Poland and in the top 20 across a spectrum of cultures who you would hope would know better.

America's most broadly influential cultural export, music, has in the opening stages of the decade infected the world with the LMFAO virus, one whose lyrical thrust is joy through hedonism — ridiculous celebratory anthems and occasionally funny male fantasies of sexual magnetism earned through a combination of, in the words of its 2009 anthem "Shots": "Jägerbombs, lemon drops, buttery nipples, Jello shots," and good old-fashioned gin.

Few will mistake Redfoo and SkyBlu for Leiber and Stoller. But within the group's sound lies an interesting sonic history, even if it's often eclipsed by the stupidity, and regardless of whether they prove every last non-party-rockin' critic right and vanish tomorrow, a document of their existence seems warranted. They are, after all, the son (Redfoo) and grandson (SkyBlu) of Motown Records founder Berry Gordy Jr., are Grammy nominees, have a combined YouTube viewing tally of almost 800 million, and have another single rising on the charts.

How ridiculous/clumsy are their words? A fine line, it has been said, separates stupid from clever, but Redfoo has tipped his hand by confessing in an early interview that he "failed every grade up until the fifth grade." The two describe sex play in "Party Rock Anthem" as "runnin' through [whores] like Drano" in one of the least seductive lines in recent pop music memory. "Sexy and I Know It" is nothing more than a four-minute sexual boast — with a funny video set in Venice Beach involving an impressive (cod-pieced) thrust-off between Redfoo and SkyBlu.

But erase the lyrics from their string of hits — "I'm In Miami, Bitch" (about getting drunk on the beach), "Shots" (about getting drunk fast), "Party Rock Anthem" (about partying), and their new single, "Sorry for Party Rocking" (about how they're sorry that they're so enthusiastic about life that they can't help partying nonstop) — and you can see the foundational DNA of a uniquely American strain of electronic dance music, one that combines a bunch of weird regional American variations into one frenzied, sexually charged whole.

Most prominently, the sound of LMFAO is a much beefier, on-steroids version of Chicago booty house and Detroit electro — subgenre riffs on the genetic building blocks of modern-day dance music, house and techno. Also embedded, consciously or not, is the Miami bass sound of Maggotron, 2 Live Crew, Tag Team, the bum-jiggling thump of New Orleans bounce, Baltimore club and Atlanta crunk. It's a sound that has at its base the Roland TR-808 drum machine, has thrived within little African American subcultures since the rise of house music in the mid-1980s, and is typified by its bawdy, over-the-top boasts and come-ons. If you're looking for lyrical clarity, you can't get any more direct than Detroit ghetto-tech producer DJ Assault's frantic "Drop Dem Panties" or DJ Deeon's booty-house scream-out of Chicago, "Shake Dat Butt."